Continuously rising nitrate and phosphate levels / Snail invasion


I have a question about the phosphate and nitrate levels: I have a 180 liter tank in which the nitrate and phosphate levels continuously rise. I did not find a dead fish.

these pollution parameters are partially related to pollutants from tap water, but mostly to feeding. They therefore rise quickly, especially in case of high fish stock density.

I tried to lower the values with different filter media. This only works for a short time. I change the water every fortnight.

My suggestion: add more plants and increase the water change rate (recommended: about 30 % weekly), and make sure the fresh water is low in nitrates and phosphates.

Another question (that possibly might have something to do with the above mentioned problem) is: I have a real snail problem. There is snail spawn on almost every plant. I keep collecting the snails, but they multiply extremely fast.

There is quite probably indeed a connection - too much food! Accordingly, you can reduce and prevent snail invasions by considerably reducing fish stock and food amount.

Best regards

sera GmbH

Dr. Bodo Schnell


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